XS15 - Pam3Cys-GDPKHPKSF

The adjuvant XS15 is a water-soluble TLR2/TLR1 ligand inducing strong CD8 and TH1 CD4 response against free short peptides emulsified in Montanide™ ISA 51 after a single s.c. injection. It was shown that the granuloma induced by injection of a mixture of short synthetic peptides and Montanide™ shows high concentration of functional antigen specific T-cells that produce IFNy, TNF, and IL2, CD8 cells also produce CD107a, but no IL10 [1]. High frequencies of antigen specific T-cell were also found in the peripheral blood. XS15 supports potent T-cell response in a COVID-19 peptide vaccine [2,3].

The lipopeptide is provided as a endotoxin-free, lyophilised, colourless powder without any additives. It can be shipped at room temperature an the lyophilized powder should be stored at +2°C to +8°C. XS15 can be reconsituted in endotoxin-free water (1mg/mL stock solution). 

XS15 is recommended for immunisation in combination with Montanide™ IA 51 (SEPPIC GmbH Köln, Germany) [4] to generate a strong immune response against free short peptides.

Recommendation for immunising mice: 300µg antigen plus 50µg (1mg/mL solution) Adjuvant XS15 plus 100µL Montanide™ ISA 51.

Reference:
[1] H.-G. Rammensee, K.-H. Wiesmüller, P. A. Chandran et al. (2019) A new synthetic toll-like receptor 1/2 ligand is an efficient adjuvant for peptide vaccination in a human volunteer. J. Immunotherapy Cancer 7, 307 doi:10.1186/s40425-019-0796-5.
[2] H.-G. Rammensee, C. Gouttefangeas, C. Heidu et al. (2021) Designing a SARS-CoV-2 T-cell-Inducing vaccine for high-risk patient groups. vaccines 9, 428. https://doi.org/10.3390/vaccines9050428
[3] J.S. Heitmann, T. Bilich, C. Tandler et al. (2021) A COVID-19 peptide vaccine for the induction of SARS-CoV-2 T cell immunity. Nature, doi.org/10.1038/s41586-021-04232-5. (Accelerated Article Preview Published online 23 November 2021)